Dash Gauge Summary Accuracy

[dsmith17]

Looking at the 2017 Ram 3500 SRW 4x4 CC LB and wanted to know how accurate are the Gauge Summary outputs (under Vehicle Information dash display).

Things like trans temp, coolant temp, oil temp, oil pressure?

I've got full-sweep mechanical AutoMeter gauges on my current truck. The use of monitors to display data from ECM is new to me. But very impressive capability.

Does the truck computer provide accurate temps and pressures? I've read some folks report that the readings are determined by "algorithms"
(i.e., not by actual sensors placed at the source).

Do folks no longer use mechanical gauges on these modern diesels? Or only for some things (like EGT and trans temp)?

Many thanks!

 

[jhenderson]

Water and trans temp are actual and by all reports from FCA techs quite accurate . Oil temp and pressure are algorithms derived from calculations made by the ECM. I've never seen reports on oil temps but oil pressure readings from mechanical gauges vary quite a bit from EVIC readings.

 

[dsmith17]

Thanks, jhenderson.

For the modern diesels is the following a good monitoring solution:

(1) EGT probe and mechanical gauge
(2) dash-mounted Monitoring device (similar to Edge or Bully Dog Watchdog)

Any other manual gauges recommended?

Many thanks,
Dave

 

[jhenderson]

If you plan on remaining stock an egt is superfluous.

 

[dsmith17]

My stock '99 F-250 7.3 PSD that I've been driving for 18 years has four full-sweep Autometer gauges on the pillar (EGT, trans temp, water temp and boost). These have been critical for me over the years towing our 36-ft 10K# travel trailer...especially on Togwotee pass on Hwy 287 via I-80 in Laramie to Rawlins, Wyoming! As EGT's would approach 1200* the coolant temp would steadily creep past 240+ which FINALLY would cause OEM water temp dash gauge to budge off "normal" and move up to red!!

Some of the factory gauges are about useless (e.g., water, oil pressure) in providing any real information (they stay pegged in one position as long as within broad operating range). Guess I've gotten comfortable in having gauges that provide realtime info of what is going on under the hood.

Of course these diesels today have just slightly more HP and torque than my Aug. '98 production truck!

 

[apgambino]

For what it's worth the temp gauge on my 15 3500 seems to move linearly with the coolant temp. When it's warming up it will finally register at about 150 degrees. 200 degrees seems to be midway. Coming back from Ventura this afternoon on I5 towing my 16.5k toy hauler I noticed the gauge moved well above the middle when the EVIC said the coolant was at 235 or so right before the fan kicked on. Once it did you could actually see it drop quite quickly.

 

[SnoKing]

Put fuel and DEF in it and drive it. These new trucks reportedly will not hurt themselves.

SNOKING

 

[dsmith17]

Thanks, y'all.

Hey, how do y'all like your 3500 SRW suspensions? How's the ride when not loaded but just driving around town empty?

Have y'all added any aftermarket products to soften the ride (e.g., Sulastic shackles)?

I am REALLY liking the Ram Cummins/Aisin in 3500 4x4 and Megacab setup!

Thanks again!

Dave
Austin, TX

 

[apgambino]

Thanks, y'all.

Hey, how do y'all like your 3500 SRW suspensions? How's the ride when not loaded but just driving around town empty?

Have y'all added any aftermarket products to soften the ride (e.g., Sulastic shackles)?

I am REALLY liking the Ram Cummins/Aisin in 3500 4x4 and Megacab setup!

Thanks again!

Dave
Austin, TX

That's the exact setup I have. I find the ride unloaded to be a bit rough, but I knew that going into it. I could lower my tire pressure a bit, but I mainly use the truck for towing my 5er so I keep them 80 psi in the rear. When I am towing the truck rides much better.

 

[jhenderson]

Guess I've gotten comfortable in having gauges that provide realtime info of what is going on under the hood.

Of course these diesels today have just slightly more HP and torque than my Aug. '98 production truck!

Comparing 20 year old tech with today's has little value. The gauges that do read directly, water, trans, boost etc surpass even your aftermarket in accuracy and reliability.

 

[SnoKing]

Lower the rear tires to 45 lbs empty and ride improves greatly. I have a latch on air chuck that I latch on without the hose connected to let air out. Which makes deflating easier.

http://www.oreillyauto.com/site/c/d...N2373_-1_-1&pt=N2373&ppt=C0337#itemDetailTab_

Both of these standard RAM tires follow the same industry standard inflation table. SNOKING

LT275/70R18 and LT285/60R20
PSI RATING
35 2070
40 2270
45 2470
50 2680
55 2840
60 3020
65 3195
70 3360
75 3530
80 3640

So at 45 lbs/2470 rear axle still has 4940 capacity. Leaving 1000-1500 load capacity for casual hauling.

SNOKING

 

[dsmith17]

For what it's worth the temp gauge on my 15 3500 seems to move linearly with the coolant temp. When it's warming up it will finally register at about 150 degrees. 200 degrees seems to be midway. Coming back from Ventura this afternoon on I5 towing my 16.5k toy hauler I noticed the gauge moved well above the middle when the EVIC said the coolant was at 235 or so right before the fan kicked on. Once it did you could actually see it drop quite quickly.

apgambino, once your fan kicked on what did your coolant temp drop down to (from 235*)?

 

[dsmith17]

Comparing 20 year old tech with today's has little value. The gauges that do read directly, water, trans, boost etc surpass even your aftermarket in accuracy and reliability.

Right on! Thx!

 

[dsmith17]

Lower the rear tires to 45 lbs empty and ride improves greatly. I have a latch on air chuck that I latch on without the hose connected to let air out. Which makes deflating easier.

http://www.oreillyauto.com/site/c/d...N2373_-1_-1&pt=N2373&ppt=C0337#itemDetailTab_

Both of these standard RAM tires follow the same industry standard inflation table. SNOKING

LT275/70R18 and LT285/60R20
PSI RATING
35 2070
40 2270
45 2470
50 2680
55 2840
60 3020
65 3195
70 3360
75 3530
80 3640

So at 45 lbs/2470 rear axle still has 4940 capacity. Leaving 1000-1500 load capacity for casual hauling.

SNOKING

Excellent tip! Thank you!

 

[apgambino]

apgambino, once your fan kicked on what did your coolant temp drop down to (from 235*)?

It would take it all the way down to under 200 over the course of about 10-15 seconds while under a decent load going up a 5% or so grade.

 

[Cummins12V98]

Add the Factory Rear Air option, IMHO it'w worth every $$$.